1. Field of Invention
Embodiments of the present disclosure relate to a semiconductor device and an operating method thereof, and more particularly, to a soft program operation after an erase operation.
2. Description of the Related Art
Nonvolatile semiconductor memory devices can retain data even without power. NAND memory devices, which are a type of nonvolatile semiconductor memory, are able to achieve large storage capacities with low power consumption. Therefore, NAND memory devices are frequently used in notebook computers, mobile devices, etc.
Nonvolatile memory devices can be classified into two-dimensional nonvolatile memory devices and three-dimensional nonvolatile memory devices depending on the memory cell string structures. In two-dimensional memory devices, the strings are parallel to the substrate. In three-dimensional memory devices, the strings are perpendicular to a substrate. That is, three-dimensional nonvolatile memory devices have vertical channel layers arranged perpendicular to the substrate, memory layers surrounding the vertical channel layers, and word lines stacked and spaced apart along the memory layers.